1. Field of the Invention
This invention relates to an improved meal delivery system and to a method for delivery of pre-cooked, chilled meals from a central distribution station to a plurality of remote locations, and in particular to a one-piece, molded, insulated meal delivery cart for transportation of chilled meals in cooperation with an Automatic Guided Vehicle (henceforth xe2x80x9cAGVxe2x80x9d) system.
2. Prior Art
Our population continues to increase and age at a rapid rate. Many people are now confined in, cared for, or work in large institutions and government-sponsored operations, such as prison facilities, mental health facilities, hospitals, and military bases. One notable demographic trend is a marked increase in the number and size of prison facilities in the last twenty years. The greatly increased physical size of prison facilities and the unprecedented increase in the number of inmates housed in them has created many new challenges, including how to provide a large number of persons with proper daily meals reliably. Moreover, in a prison setting, providing the inmate population with decent meals on a regular and reliable schedule reduces tension and generally eases management pressures.
Many prison designs incorporate multiple housing units which may be geographically separated from each other by substantial distances. In these facilities, the difficulty of providing meals for the inhabitants is exacerbated. One approach for meal provision in multiple-unit facilities has been to equip each separate housing unit with its own kitchen. Meals are prepared in each unit""s kitchen for the inmates in that unit. Such a one-kitchen-for-each-unit configuration presents unique logistical problems, requires staffing redundancies, and is very expensive to maintain. Indeed, new construction of facilities incorporating a kitchen in each separate housing unit can be prohibitively expensive. Expense notwithstanding, it is an undesirable inefficiency.
Another approach has been to provide a central kitchen for preparation of meals which are then delivered to each separated housing unit. Health standards require meals to be fresh, hot portions to be hot, and cold portions to be cold, when served. Any delays between cooking and service allow the hot portions of prepared meals to cool, the cool portions to warm, and the entire meal to become stale, posing a potentially serious health risk.
Substantial savings have been realized by use of an AGV system for automated delivery of meals from a central kitchen by carrying carts stocked with meals on preestablished paths to separate housing units. An AGV system establishes predetermined paths by used of an embedded guidance system, such as a wire. Battery operated carrier vehicles ride on surface tracks above the guidance wire. Each carrier vehicle is programmed to move along a path from a docking station at a central distribution point, e.g., adjacent the central kitchen, to a loading dock adjacent each housing unit. Each carrier vehicle includes a flat top movable between a lowered rest position and a raised carrying position. Each delivery cart has a bottom surface slightly higher than the height of the lowered position of the carrier vehicle, but lower than the raised position. Communication between an operator and each carrier vehicle is accomplished using infrared signals. Accordingly, in normal operation a system programmer communicates a path to a particular housing unit to the carrier vehicle. A meal delivery cart filled with meals for the selected housing unit is moved into position at the central docking station. The carrier vehicle then rolls into position at the docking station underneath the delivery cart. Raising the top of the carrier vehicle lifts the delivery cart. The carrier vehicle then carries the delivery cart along the designated path to the selected housing unit. In this manner delivery of thousands of meals to separate housing units may be achieved with a substantial savings in labor costs previously required to hand deliver prepared meals.
In the prior art, meals prepared in a central kitchen are separated into their hot and cold portions and transferred to meal delivery carts for disbursement to housing units. Prior art meal delivery carts suffer numerous disadvantages, including being very heavy, each weighing as much as 3,500 pounds empty. They are difficult to maneuver and experience frequent, expensive breakdowns. Each cart has separate electrically-powered heating and refrigeration compartments. Cleaning the carts with water damages the heating elements and the compressor. The electrical heating and refrigeration components require constant maintenance, consequently removing carts from active service. Numerous moving parts create a litany of maintenance issues. For example, outwardly swinging doors require frequent repair. Accumulated mechanical problems associated with prior art carts have been known to take as much as thirty percent of the carts out of service at any time.
Maintenance issues aside, in normal use of prior art meal delivery carts, once meals are cooked and prepared in the central kitchen, hot portions are placed in the heated compartment and cold and cool portions placed in the refrigeration compartment of each cart for transportation to the housing units. Once at each housing unit, the cart must be brought inside and plugged into an electrical outlet to power the heating and refrigeration units. Delays from the time the carts are initially loaded with meals to the time the cart is plugged into the electrical outlet result in hot portions cooling and cold portions warming. Prior art food delivery carts are poorly insulated, allowing meals to warm or overheat quickly on hot days. Prior art food delivery carts also incorporate metal surfaces which quickly pick up solar energy and ambient heat. Meals left for too long in the heated compartments dry out. Meals left for too long in either compartment deteriorate and become stale.
An additional complicating factor is that any vehicle used for delivering food or other products is subject to tampering, abuse, and simple neglect. Particularly in a penal institution, tampering is of real concern because the path of the cart may take it through various areas in which it is unattended. Flat tops on the existing carts allow contraband to be anonymously carried from one point to another during transportation.
Each prior art food delivery cart has a capacity to hold only 48 complete meals. Accordingly, delivery of 100 meals requires three cart trips to the housing unit; delivery of 300 meals requires seven trips.
Finally, the cost of manufacturing new and replacement food delivery carts must be acceptable within the budget guidelines of the governmental agency or other supervising authority having responsibility for management of the institution. Purchasing new carts is expensive, costing approximately $18,000 for each new cart.
One successful technique for delivering fresh, hot meals from a central kitchen to outlying facilities is the xe2x80x9ccook-chillxe2x80x9d method. Under the cook-chill method, hot portions and xe2x80x9ccoldxe2x80x9d portions are prepared in large quantities in a central kitchen and immediately chilled, but not frozen, for storage in the kitchen refrigeration units. Such chilled meal portions can be safely and successfully stored at temperatures between approximately 35xc2x0 F. and 40xc2x0 F. for periods of time varying from one week to over a month depending on the particular food. As needed, individual food portions can be removed from storage to assemble complete meals for delivery to remote housing units. Unfortunately, prior art food delivery carts do not readily lend themselves to delivery of cook-chilled meals. A further problem is the lack of heating and refrigeration facilities in each housing unit.
Accordingly, a need exists in an institutional setting, particularly in penal facilities, for a food delivery system for transportation of meals from a central kitchen to outlying housing units, in cooperation with an AGV system that can deliver meals which are fresh and hot, has increased capacity, is tamper-resistant, and is less expensive to acquire and maintain.
Applicant""s invention relates to an improved meal delivery system for delivery of meals from a central distribution point to a plurality of remote housing units in cooperation with an AGV system. Accordingly, applicant""s invention provides a plurality of improved meal delivery carts for transportation of cook-chilled meals, and a refrigeration unit and an oven in each housing unit for refrigerated storage or heating of the cook-chilled meals.
In accordance with the invention, a plurality of meal delivery carts are provided, each comprising an insulated enclosure mounted on a wheeled chassis. Two insulated doors close off an interior storage space which is sufficient to accommodate up to two hundred and eight cook-chilled complete meals. Each enclosure and each door is insulated with foam insulation during the manufacturing process using a rotating mold technology to inject insulation between the walls of the enclosure and the door. The enclosure and both doors are sufficiently insulated to maintain a full complement of cook-chilled meals, pre-chilled to approximately 35xc2x0 F., which have been placed in the interior storage space, with doors closed, at a temperature of no greater than 40xc2x0 F. for one hour in 100xc2x0 F. ambient conditions in direct sunlight. Thus, chilled meals can be safely transported in the cart from a central kitchen facility to a remote location all the while maintaining the meals at an acceptable temperature.
Each enclosure is a single molded unit. Similarly, each door is a single molded unit and, because each door is manufactured from the same mold, each door is identical to the other. Accordingly, the enclosure and doors require only two moldsxe2x80x94one enclosure mold and one door moldxe2x80x94which facilitates the manufacturing process and makes replacements for broken or defective enclosures or doors readily available. The enclosure and doors are manufactured using high-impact polyethylene making them durable, impervious to water, and less amenable to absorption of solar radiation. The enclosure and chassis together weigh approximately 1,500 pounds empty, 3,500 full, making them considerably more maneuverable.
The enclosure doors are disposed in top and bottom raceways for sliding from side-to-side. Manufacturing the enclosure and doors from one mold each results in reduced overall production costs, especially over the long term once the molds have been purchased, and greatly facilitates repairs by speeding and simplifying production of new enclosures or doors as they may be needed. Each door has a leading edge and a following edge which is thicker than the leading edge. When the doors are in their closed positions, the following edges overlap in sliding abutment, sealing the interior storage space.
The floor of the enclosure is provided with drainage troughs to allow the interior of the enclosure to be hosed out, minimizing the time and effort needed for cleaning.
The wheeled chassis provides a channel through which a carrier vehicle of an AGV system can drive. The enclosure includes a flat bottom surface for riding on the top flat surface of a carrier vehicle. Accordingly, a meal delivery cart according to the invention may be placed in a docking station where a carrier vehicle may then be brought into position directly thereunder for picking up the cart.
The overall construction and design of the cart provides essentially no horizontal surfaces which could be used for unwanted transportation of contraband. The single mold construction of the enclosure and doors provide smooth continuous surfaces lacking breaks or openings where objects can be inserted for illicit traffic. The roof of the enclosure is slanted at a steepness which does not allow objects to be placed on it. The base of the enclosure mates with the chassis to present a smooth surface underneath the enclosure. Each door is provided with a lock preventing the doors from being removed from the enclosure. The cart is also equipped with anti-tipping brackets to prevent it from being pushed over. The features of the cart thus greatly discourage tampering.
At each remote housing unit meals or meal portions may be stored in a refrigeration unit. When needed, hot portions are removed from the refrigeration unit and heated in warming facilities. When the hot portions are ready, they are assembled with the cold portions for immediate service as a complete meal.
It is therefore a primary object of the invention to provide an improved meal delivery system for transportation of cook-chilled meals from a central kitchen facility to outlying or remote locations while at all times during transportation maintaining the meals chilled at a safe temperature.
It is another object of the invention to provide an improved meal delivery cart for transportation of cook-chilled meals from a central kitchen facility to outlying or remote locations while at all times during transportation maintaining the meals chilled at a safe temperature.
It is a further object of the invention to provide an improved meal delivery system for transportation of cook-chilled meals from a central kitchen facility to outlying housing units while at all times during transportation maintaining the meals chilled at a safe temperature.
It is yet another object of the invention to provide an improved meal delivery cart which comprises a one-piece enclosure having single-unit molded identical, reversible doors defining an interior storage space which is durable, impervious to water, and light weight in comparison to prior art meal delivery carts.
It is a further object of the invention to provide a tamper-proof meal delivery cart which is insulated to allow cook-chilled meals to be transported from a central distribution area to outlying housing units for reheating and service.
It is a still further object of the invention to provide an improved meal delivery system for transportation of cook-chilled meals, at all times during transportation maintaining the meals chilled at a safe temperature, from a central kitchen facility to outlying or remote locations each having a refrigeration unit for chilled storage of the meals, and a oven for reheating of the meals for service.
It is another object of the invention to provide a meal delivery cart which is easy and relatively inexpensive to manufacture and wherein the manufacturing process allows quick and easy replacement of broken or defective parts.
It is another object of the invention to provide a meal delivery cart capable of transporting up to 208 individual pre-cooked meals, chilled to approximately thirty-five degrees Fahrenheit, having a storage space sufficiently insulated to maintain the temperature of such chilled meals at no greater than forty degrees Fahrenheit for one hour in one hundred degree Fahrenheit ambient conditions in direct sunlight.
It is a still further object of the invention to provide a meal delivery cart having smooth exterior surfaces and having easy to clean interior and exterior surfaces.